When liquid travels from one material to another it usually changes direction. Lenses use this principle, but are usually made from glass or plastic. Solids do not easily change shape and so the strength of these optical devices are fixed by their manufacture.
Our experiments use liquids and shape their surfaces using a voltage to create liquid optical elements. These can be lenses using a droplet of oil or more complex diffractive devices to beam steer using a film of oil with a wrinkled surface.
The apparatus used to produce the diffraction pattern at the top of this page can be seen in the video below:
Developing interface localized liquid dielectrophoresis for optical applications
G. McHale, C.V. Brown, M.I. Newton, G.G. Wells and N. Sampara
Proc. SPIEE 8557 (2012) art. 855703.
Voltage-programmable liquid optical interface
C.V. Brown, G.G. Wells, M.I. Newton and G. McHale
Nature Photonics 3 (7) (2009) 403-405.
(also see the Editor’s interview)